Tune ups in the original sense of the word are somewhat a thing of the past. As breaker point ignition, distributors and carburetors were replaced, the term that serviced them stuck with us. In the past these mechanical items required frequent cleanings and adjustments. While much of the adjustment work is now computer controlled, still carbon cleaning and routine service remains a necessity
Major advancements in technology have us spoiled driving cars that don't need to be "tuned' like they did in the days of the origin of the "tune up" term. A multitude of sensors communicate data to a high powered computed that can make micro adjustments as components wear and even as we drive. That being said there are still a few items that require routine periodic service.
The carburetor has been replaced by a group of sensors, a computer, fuel injectors and a throttle body. While the computer has a map to adjust the throttle and injectors there is some required maintenance. The throttle body as well as the intake chamber system will develop deposits of excess unburned oil and gas. At the minimum these deposits must be cleaned every 30,000 miles, GDI (Gasoline Direct Injection) engines will require service every 15,000 miles to prevent major internal repairs.
Gone are the days of adjusting breaker points and cleaning fouled spark plugs! Spark plugs on your engine will still wear out, while the fuel mixture calculation is adjusted so precisely the wear will be barely noticed and the replacement will not be until 60,000 miles! Don't wait until you have a running problem to perform this maintenance. Not replacing a worn spark plug will cause added strain on the remainder of the secondary ignition system and eventually cause ignition coil failure, a more expensive repair in comparison with the routine maintenance.
Following completion of these maintenance items the service technician will reset the vehicle onboard computer so that the optimal performance is adjusted.